emery



1,599,561 A. B. EMERY CONCENTRATION OF ORES Filed Dec. 5, 1922 2sheets-sheet 1 IN VEN TOR ATTORNE Y6 Sept, 14 1926;

Sept. 14 1926. 1,599,561

A. B. EMERY CONCENTRATION OF ORESV Filed Dec. 5, 1922 2 Sheets-Sheet 2J/ M12 nvwgoR a (B 7 BY 6 A TTORNE Y6 Patented Sept; 14, @1926. p

iorralice.

' Li 'jmeusmvs BACHELDER M R ;ol mnssnm;"iR iqsvAAL, SOUTH AFRICA."

.7 vc nceitTR ATIQa [oneness Application fiiled p qell lbjr jsf 'ez';Serial 1%. truism, a s a scam itfiriea Septembelf21,1922;

This inventionrelates to the concentration of ores, andhas tor itsobject the pm 'f vision of a newl' and iniproved method "of andapparatus for the concentration of ores by flotation. T {The presentinvention oonten'iplaftes'certain improvements in the present custoniarymethods of 'concentratinggores by flotation.

In general, these inethodsinvolve the fun-I damental feature of piodu'cinga frothlpossessing selective attraction orf preference for/themetalhferousfparticles of anore pulp in contradistinction to 'Ythegangne particles thereof. For theformati'on of the I p p v I ijthroughthe vessel. The circulation 1 of senti'al and in the pres t t froth,fair '01 other appropriate" gaslis fesmethods offiotation, 'sueh air isobtainedby agitation or aeration 1 or by a combination of,aeratio'n'f'and agitation of the oie pulp] The improvements contemplatedby as p'ij'esent invention-involve more particularl animprovedjniethedof and-improved appa ratiis for bringing about the (necessaryinter-action between the ore pulp; and air or other appropriateflg'asfor the productlon of a nineral bearing' froth.

accordance with one aspect offth'e present inventioman ore pulpycontaining an appropriate flotation ag'enhis caused, in' I I I conunct'loin with the accompany mas, n which the presence of air for; otherappropriate gas and in the form ofa inultlpl citjrv ot 'sniall againstfahaliling sn'rfafce'wvith sufficient ing froth.v Thus, the separatedstreams orjets o tore pulp may he projected'againstra" effectively j Ibathing surface adapted; to break up or atoniiz 'e the same in agas-filled space, which may advantageonslyf he; a spaceflcontalnlng,atmospher c air. The b th con mineral-bearing frothforin'ed isi' in accordance 'vvlt-hfthe preferred practice invention"trapped beneath vthe. surface of the inain" body or the ore p'nlpand}is )re covered from a relatively quiescent Zone of 5 the ain bod oforejpulp'. Preferably, the ore pulp is circulatedwithin an appropriate;receptacle, in the course 'o f'vv'h'ich circ'nla-h ftion the ore pulp iselevated tofaheight above the normal "operatingore phlplevel in thereceptacle and discharged back; into th'e'receptacle in the formfoti'elativelyfin'e;

streams which arve" intercepted the ,sur 3f; e ot; the" ore pulp ie thereceptacle Q or by;

i by transverse 'pafl 'titions 11 into a; plnrali an appropriatelypositionedlhafile with su t"- f cient violence to effectively break upthe ore pulp" streams in the presence of air'or other, appropriate gasWith the attendant formation ofa mineral-bearing froth. it

The improved apparatus of the invention the ore pulp in each receptacleor cell of, the apparatus -;1s carried out in the inanner ,ivhich'characterizes my in] inventionwvill hefhetter understood froi'nfthe'folloiving discription taken 4 in draw :1 i s fan: elevation partly ,insection of -ed appai"a-tns of the invention fl ig '2 i's a ssectionalelevation of the apparatusof ig..' 1'; taken on the section line Fig.-

i's'an elevation partly in section ofthefldislcharge endofthe apparatus;

Figi' l" is a partial top-plan oi the a'pparafl tug}. p p v 1F .g5fandl6are detail viewsillustrating thejia'ccoinpanying {drawings comprises anelongated vessel 10 jchv ded longitudim a, The improved apparatus,illustrated iii. I 100 I struetion lot the neumatic? piilp ele vating'neansj r of separate receptacles' or cells. Thus, the

' vessel ma be divided into'ten (or more or less) such" receptacles.-The partit ons 11 are ZOI IStIlIQlLBCl n two parts with an appropriate'space} 12 between the upper and lower; parts :to permit of; the desiredflow v.

, of ore pnlp nee-one receptacletofthe next; "In cross section' 'thefvessel-[101 s Vo-shaped in its lower portion and rectangular in itsupper portion. t I j .An' oblong shaped conduit formed by side members13 and end members 1 1 is centrally dn posed in each receptacle ofthevessel 10. The lower end of each conduit is open and in freecommunication with the receptacle near the bottom thereof, while theupper end ts inmates boa having a pluralityof orifices or nozzleopenings in each side thereof and closed at the top by a cover #8. Theoblong conduits are longitudinally disposed their respectiye receptaclesand; are guided into their operative positions by guide cleatsetasecured to the partitionsll ai d guide blocks 46 on the lowerfiaredportions of the conduits; Theconduits are suspended or hung in positionby means of strips or bars 17 secured to the end members 11 of theconduit and resting upon'the tops of thepartitions 11. The side members13 are outwardly flared at their bottoms so'as to catch all of the airdiscliargedfrom the air distributor as. hereinafter more fullydescribed. f

A pipe 16 is centrally disposed in each of the oblong conduits andterminates at its lower. end a cylindrical air distributor 17. The pipes16 are connected at their upper ends to an air. supply main 25.

Each air distributor 17 ismade'up of a cylindrical tube 18.'liavi1ig itsends closed by circular caps 19 held 'together by a bolt 20. The tube 18is provided with a plurality of holes 21. The perforated tube 18' isexternally surrounded by oneor more layers 22 of line wire screen orloosely woven cloth such, for example, as burlap, or gunny-s ack cloth.A clamping frame 23 serves to operatively connect the air distributor tothe.

pipe 16 whereby the interior of the tube 18 is placed in communicationwith the pipe'16.

The fair distributors 17 rest upon the bottoms of the receptacles in thevessel 10 and are held in their operative positions ,loy means of guideblocks 24. The air distributors are positioned directly beneath thelower open and flared ends of their respective oblong conduits. Avertical partition'or bafl le 26 1s arranged on each side of the oblongconduit ineach of the receptacles of the vessel 10. The partitions 26are operatively held in'jplace between a fixed cleat 2'7 and a removablecleat 28, the latter being held in position by the clamping actionvbetween a fixed taperedblocli 29 and a removable tapered block 30. Thelowerends of the partitions 26 extend a .short distance below the normaloperating ore pulp level in their respective receptacles and serve to dvide each receptacle (on each side of the central oblong conduit) intoan inner frotlrforinin'g' compartment and an outer; froth-collectingcompartment.

hach s de of the vessel 10 is provided with launders 31 for collectingand carrying away the froth overflowing the sides of the frothcollectingcompartments of each receptacle. The froth overflow height of anyfroth-collecting compartment may be appropriately adjusted by means ofremovable strips 32 operatively held in position by the clamping ac tionofa fixed tapered block 33 and a removable tapered block 3%;

The launders 31 are preferably arranged to separately collect the frothoverflow of particular receptacles. Thus, the froth overflow fromcertain receptacles near the feed end of the vessel may be separatelycollected from the froth overflow from the other receptacles of thevessel. I v

A pair of feed pipes 35 are arrangedfor the introduction of ore-pulpinto the first receptacle at the feed end of the vessel. At

the dischargeend of the vessel, the ore pulp 36 is provided with adischarge opening adapted to be closed by a valve 38. The overflowdischarge from the compartment 36 flows into a box 39 which is suspendedby means a rod 410 and spring &1 and which has, at its lower end, adischarge spigot 42. A lever arm 13 is secured at one end to a finedpartof the vessel 10 and at its other end to the box 39 and intermediateits ends to the valve 38. A discharge pipe se is provided for carryingaway the tailiiigs discharged through the bottom opening in thecompartment 36 and the spigot in the suspended box 39. j I j In carryingout the improved method of the invention in the apparatus illustrated inthe accompanying drawings, a suitably prepared ore I pulp containing an.appropriate flotation agent is introduced into the first receptacle orcell of the vessel 10 through the feed pipes 35. Air or otherappropriate gas, undersuitable pressure, is introduced into the airdistributors 17 and enters the ore pulp in a relatively fine state ofsubdivision directly beneath the flared lower end of the oblong conduitin each receptacle. The air rising in these conduits exercises an airlift action and causes an upward flow of ore pulp through theconduitswith the attendant discharge of the ore pulp through the nozzlesor orifices 15. I The ore pulp is discharged through the orifices ornozzles 15 in the form of amultiplicity of, small separated streams orjets which impinge upon the surfaces of the partitions or baffles 26 orthe top surfacewoffthe main body of orepulp in the receptacles, or both,and are eeaselr is; Qat once driyen .gdownwardly j and ou wardlylunderthe bottom edge of the part tions, 2 6', and; the froth then risesgin.the f frothll ing omp e nlthm h t below, thus forcing up the gas bubblesreig side ofthe partitions',-26dand overflows into 'the laundersfii.There nainder of the ore pulp from whlch theisjulfides:have'been n largepart eliminated (bybeing caughtin; he; f eth.) c u e's owar th b nmt thereceptacle and in, part passes onv to the ,;0re pulp, graduallyworksitsavay through t-r l pera e a 38; wh l theia m I and Water riseandoverflow the adjustable 5. Y;Weir,37 into the movable box '39. Ifjthe3Qsthereby increasing the Weight of the box and 35, ing in the,compartment 36, and consequently] 9 the; jets ore-' p ulp iinpinge uponit a Ihe froth is thus preseryed as fastas formed,

next succeeding receptacle and in part is" picked up by the air liftaction in the oblong conduit and a, ;ain' ejected through;

thence ales "15;; It Will thus seen-that, the

the-successive receptacles of the vessello P ssing throue h er e 12 e hp r-'1- titions. 1l and 1 being repeatedly circulated in each IGO P Q QZthef nanner. described.

receptacle. into the compartment 86 Where/the sands settle out and dropthroughthe auto ore lei el in the vessell0 rises the over,-

fiovv intolthelbox 39 Will in creasef andthis- H p 7 I flotat on can: bepromoted. in my improved increased overfloyyf will no be able to escapethrough the spig0tg4c2'and the ,boX Will fill,

contents. This increased Weig11t ill"con press zthespring Al' -and willopen more widely the valve 38, thusfincreasingthe dis-- chargeoftailings througlrthebottom openlowering the pulp levellin -the; vessel.@If

the pulp IGVQI in'the vessel falls, the reverse action, takes place,This automatic 1 "charge device lnaintainsjthe desired-pulp- ;11evelinthe vessel 10 and hasthe advantage of not requiring any handf regulation(or;

After the froth attenti'onvand of not blocking on accountof providead'jacent but. separate froth-collectating ore pulplevelgpservesto'trapthe-froth p p I v v 7 equ valent meansunay be employed, For

so that it cannot return tothe point-where ail 1 ftailing -n1aterial Vmade in the frotlrform ng compartment of :The tails are dischargedfroin'lthe last;

ias been, formed in the ,Y .zfrotheforniing compartment of; JI-liYfillle proved apparatus by the action 'ofthe ime I pinging jets of orefpulp, these same jets of orey pulp may break down ithel froth, unlessit isat oncey removed ,out of their fway j ;Thifs removal of thefrothnisaccomplished c in my. improved apparatus by means; the;arrangement of the partitions 26, 'vvhichi them down. But most importantthe fact'that the material dropped byytlic ing compartments into I whicha the froth" driven promptly" after formation The, lower edge ofithepartitionfih beingbeneath' T s s "the ore pulp pneumatically by the airlift may be used if desired. 7 circulates theorelpulp rapidly with nowea" V lows th froth-col ecting "compartment "entirely: stable and i116;gas bubbles in the frothare constantly breaking down. Atthe s'an'ie timenew froth is" constantly being a formed. The new froth crowds infroinlaunder placed to receive 1 I I I, It lsimportant to be able toaccurately and conveniently control the rate of production and dischargeof froth. If the production is too rapid, the froth illno t"cle anitself, and will carry over, With the corn centrates, a considerableamount of Wasteor The froth, when, first my improved apparatus, iscomposed of bubbles which carry concentrates inixed Withgangue. Whenthese bubbles breaklthe adhering particles are dropped and the: bubblesjust below pick up by preference the sulfide particles, letting thegangue parti'cles fall further downz until they finally reach and inixvvith the ore Jpulp. By regulating the production" and discharge of thefrotl1,-the'amount of cleaning canbe con;

its

trolled and preferential concentration by 1 apparatus, if algreatvolulne'of froth is p roduced, the velocity of the r1s1ngco1un1n offroth is rapid and the time available for cleaningnthe frothby thebrealcfdoWnpf part of, the bubbles is reduced so thatthe bubbles cancarry over-not only various column cantake place, then the bubblesfwill1 i have 'to' travela long distance before'dis- I .charged, and agreater opportunity Wlll be.

afi'orded for the'bubbles tobreak dewn and thus clean the froth.Furthermore the-great, height'of the column will in case the pres-- sureof the bubbles; also tending H of'all upper bubbles deepcoluinn ofbubbles to sassthrough before it reachesthe pulp, hence more,opportunityfor thesulfides' to caught bybubbles before finally reaching;

and becoming" lost in the pulp,

oldlhilelprefer to e rec the circulation of action hereii'ibeforedescribed, any other very little abrasion from coarse sands when thelatter are treated. Moreover, While I prefer to introduce the air intothe ore pulp through a coarsely Woven cloth, such as gun'- ny-sacl;cloth, in order to finely disseminate the air, this is not necessary andthe air may, if desired, be introduced into the ore pulp in largermasses for effcctingthe desired air lift action and the attendantcirculation of the ore pulp.

The improved apparatus of the invention enables anumber of treatments tobe given in a singlevessel with suitable provision for controllingsimply andaccurately the d scharge of concentrates from each treatmentoperation independently of the other treatmeutoperati'ons.

The improved a1 Qaratus of the invention is well adapted for thepractice differential flotation. The disc iarge of concentrates from anyone receptacle may be entirely stopped While continuous circulation ofthe ore pulp is maintained thereiii thus enabling the mixing of freshlyadded flotation agent with the circulating ore pulp. v

Owing to the absence of moving parts and (Vln to the fact that a slo )inbottom l s not depended upon for moving .the sands in the pulp, the"improved apparatus of the invention can be successfully used forconcentrating mesh or even coarser sands without causing trouble by thesands bank'- ing. Moreover, in my improved apparatus, a constant pulplevel is maintainedthroughout ineach ofthe receptacles without anyregulating device for the individual receptacles. the ore pulp simplyflowing Without throttling or other regulation from one receptacle tothe next.

From the foregoing description it will be evident that I have providedaflotation apparatus having a plurality ofcells in eacl of which the orepulp is separately circulated with the formation of a mineral-bearingfroth. This mineral bearing froth is formed by streams or jets of orepulp impinging against the surface of the ore pulp or against baffles orboth. The froth so formed is driven into a froth-collecting compartmentWhere it is trapped and prevented from returning into the froth-formingcompart-ment. In the froth-collecting compartment, the froth accumulatesand builds up, being caused to flow upwards (in a vertical column)before it is discharged with the object of cleaning? the froth by thecontinual breaking of a part of the bubbles resulting in the materialcarried by the broken bubbles being successively res'elected by fallingon the unbroken bubbles below I claim: I 1. The method of concentratingores flotation which comprises circulating an ore pulp ithin anappropriate receptacle and in the course of such circulationelevatingthe ore pulp to a height abo e the normal pulp level in the receptacle,discharging the so elevated pulp back into the main body of pulp in theform of a multiplicity of small separated streams so that the streams"of pulp impinge against a bathing surface With sufficient violence toatomize the streams of pulp in gas filled space and form a mineralbearing froth, and recovering the mineral-bearing froth so: formed".

2. The method ofconcentrating ores by flotation which comprises assihgan ore pulp through an elioi'i g'gated receptacle divided into plu:al'ity of chambers in each of which chambers there is maintained a'circulation of ore pulp iriha path substantially at ri'ght'a1ngles tothe general direc ti'on, of new of ore pulp through the receptacle andin the course ,o fsvhich circulation the ore pulp is elevated to a;height above the normal pulp level 1111' the receptacle, discharging theso elevated pulp back into the main body of pul in the form of, aplurality of small separated streams as that the streams of pulp impingeagainst abusing; surface with sufiicient violence to' effectively breakup the streamsofpul'p in a gas-filled space an'd form' a mineral-bearingfroth,

and recovering the mineral-bearing froth so formed. z

3. The method of concentrating ores by flotation which comprisescirculating an ore pulp Withinan appropriate receptacle and in thecourse'of su' clrcifculation elevating the'ore pulp to a height abovethe normal pulp leve'l'in the receptacle, discharging the so elevatedpulp back into the main body of pulp inthe form of a plurality of small.separated streamsso th at'the streams of pulp-impinge against a bafflingsurface With sufiic ient violence to effectively break up the streams ofpulp in a gas filled space and form a minera-l-bearingfroth, promptlyremoving the mineral-bearing froth from the Zone ofits formation andpreventing its return to such Zone by trapping the froth Within a'relatively quiescent Zone of ore pulp and permitting the froth to risethere in and form a froth column above the ore pulp in said quiescentZone, and recovering the mineral-bearing froth from said froth column.

4. The method ofconcentrating ores by flotation which comprises passingan ore pulp through an elongated receptacle divided into a plurality ofchambers in each of Which chambers there, is maintained a circulation ofore pulp in a path substan tially atright angles to the generaldirection of flow of ore pulp through the recep tacle and in the courseof which circulation the ore pulp is elevated to a height above thenormal pulp level. in the receptacle, dis charging the soelevated pulpback into the main body of pulp in the form of a multi- [Jlicity of"small separated streams so that "thefstreams"offpulp impingeagainst abaffling" surface {with sufhclent 'vi'olence to atomize the streams ofpulp in gas fill'ed "space and for'm' annn'eral-bearing' froth,

promptly removing the" mineral bearing "froth-iron? thezone of' itsformation and to risetherein'and form a froth "column "'ab'ove" tl1e'ore' pulp insaid quiescent zone, "and recovering the mineral-bearingfroth "l ,,I:,I,;

5. The method of jconcentrating "ores by if flotation Iwhichl'comprises' pneumatically elevating from a body of'ore pulpa-,column I I I I I I "of'sald' chambers for circulating theoref'tlier'eof, damaging the pulp near the'top of the column lathe formoffarnultiplicity of- "f'srnall separated streams against a a baffleadapted to atomize the streams of, pulp in I? "fa gas-filledspaceand'thereby; forming amine'ral be'aring froth, "and recovering theI :mineral bearingfroth'so' for'niedfi, "B-LTheinethQd of concent ratingores by j I "flotation which comprises" pneumatically elevating from abody of ore pulp a'c'olumnl thereof,- discharging the ore pulp near'theftopof'the column in" the forn1of"a multi- 1 plicity: of small separatedstreams; caus ng said streams of ore pulp to impinge against "abali'ling'surface with sufiicient violence to jatomize said streams 'ina gas-filled space ana thereby forming?a""mineralbearing 1 froth, trappig the mineral-bearing Y froth "so formed beneath ,the'" surface of thebody of ore pulp, and; rec'overing'themineralbearing froth from a'relatively quiescent Zone of said'body ofore pulp.

" 7. The "method of fconcentratin'g ore's by fiotation' Whichcomprisessubjecting an'ore 'pulp in the presence of an appropriate flotationagent to continuousretreatmentby y elevating from a body'of, the orepulp aifcol} umn thereof, continuously discharging the ore pulp near'thetop of'saidicolumn the form of a'fmultiplicityf of small separatedstreams, causing said'stre'ams of ore pulp to impinge against a bafflingsurface With sufficient violence to effectively break up said streams ina gas-filled space and thereby form a mineral-bearing froth, returningthe mineral-bearing froth and associated ore pulp'to said body of orepulp and trapping the mineral-bearing froth beneath the surface thereof,and recovering the mineralbearing froth from a relatively quiescent zoneof said bodyof ore pulp. v I I 8. An apparatus, for concentrat ng oresby flotation Which comprises a receptacle adapted to contain ore pulp,means for circulating the ore pulp in said receptacle and for elevatingthe circulating 'or'e' pulp to a height above the normal operating pulplevel Within the receptacle, means for dis- An apparatus forconcentrating ores Lbyflotation Which comprises an elongated'receptaclea'having a plurality of communi- -'cati ng'cha1nbers arrangedto permit the flow of orepulp from oneend of the receptacle *i tliroughsaid chambers to the other end of charging the" ore pulp so elevatedback into the receptacle "and against a baffling. surface in th'e'lormof a multiplicity of small'sep arate lil stre'ams sothat the streams ofore "pulp are causedto impinge against said l3tti'ill l'lgSllTfiiCWVlljhsufficient violence to. atomize' up-the streams of pulp-in a' gasiille'dspace and thereby form amineralbearing froth,v and froth-collectingmeans 'operative'ly associated With the receptacle.

the "frecept'acle, means associated with each "pulp insthe chamber in apatlrsubstanti'ally Tight angles? to he general directionbffiow'ibfdreipulp through the receptacle and for elevating thecirculating ore pulp 'to a height above "the" normal operating pulp Qlevel within there'c'eptacle, means for Cirithereceptacle, and against abaffling surface in theforniof a multiplicity of small separatedjstreams so ,thatthe'streams'of ore 10. An apparatus forconcentratingores by flotation Which-comprises a receptacle to a heightabove the'norm'al operating ore pulp level Within the receptacle, meansfor d scharging the .ore pulp so elevated back v "into the receptacle inthe form of a multiplicity'of small separated ets, me'ans Where by inthe operation of sa'id apparatus such discharged jets of ore pulpare'ca'used to impinge against a bafli'in'g surface with suf- Ificient'violence'to break up'the'jets in a gas filled; spacezand form a'mineral-bearing froth, and froth-collecting means operativelyassociated with the receptacle;

11. An apparatus for concentrating ores by flotation Which comprises areceptacle adapted to contain ore pulp, means for cir culating the orepulp in said receptacle in the course of which circulation the ore'pulpis elevated to .a height above the normal operating ore pulp level inthe receptacle and discharged back into the receptacle in the 'form ofamultiplicity of small separated jets, meanscooperating with the chargingthe o'rejpulp so elevated back into fada'pted to contain ore pulp, meansfor 'ele- -vating ore pulp from 'Within the receptacle aforementionedcirculating means'whereby v in the operation ofthe apparatus saiddischarged jets of orepulp are caused to im-.

pinge against a bathing surface: With suf- 'ficient violence'to break upthe jets in' a s gas lilled space and form amineral-bearing .wit-hin thereceptacle, meansfer etli'ecting an upward flow of ore pulp in said conia frot -C lec g m ans op atively associated with the receptacle.

13. An apparatus for concentrating ores by flotation which comprises areceptacle adapted to contain ore pulp and'having afroth-formingcompartment and a froth-coll ec-ting compartmentcommunicating therewith'below the normal operating ore pulp level in thereceptacle, means for circulating the ore pulp in said receptacle in thecourse of which circulation the ore pulp is elevated to a height abovethe normal operating ore pulp level in the receptacle and dischargedback into the receptacle in the form of a multiplicity of smallseparated jets, 'means whereby in the operation of said apparatus suchdischarged jets of ore pulp are caused to impinge against abafilingsurfaCe adapted to atomize the jets of ore pulp in a gas-filledspace, and froth-collecting means operatively associated with saidfroth-collecting compartment. I

14:. An apparatus for concentrating ones by flotation which comprises areceptacle adapted to contain'ore pulp, an'upright'conduit within thereceptacle having a lower open end arranged near the bottom of thereceptacle and terminating at its upper end in a plurality of relativelysmall 'orificesat a height above the normaloperating ore pulp level.within the receptacle, said orifices being adapted to direct ore pulpdischarged from the upper end of said conduit back into the receptacle,pneumatic means oper atiiiely associated with said conduit for efiectingan eaaas upward flow of ore pulp therein, means whereby the ore pulpdischarged through said orifices is caused to impinge against a bathingsurface within the receptacle, and froth-collecting means operativelyassociated with the receptacle.

15. An apparatus for concentrating ores by flotation which comprises areceptacle adapted to contain ore'pulp, an upright battle arranged toprovide in the upper part the receptacle, a froth-collecting com- Acompartment.

16. AL/5X11 apparatus for concentrating ores by flotation whichcomprises a receptacle adapted to contain ore pulp, an upright conduitwithin the receptacle having a lower pe and nea he bo t m of th e pta land terminating at its upper end 'ina plua i yvi re at r ly mal o i esare e s above the normal operat ng ore pulp level within the receptacle,means for introducing into the lower cpen end of said conduit air in astate of relatively fine subdivision and thereby effecting an upwardflow'of ore pulp through the conduit and out of the orifices h re flmeans w er by in he p ratio of said apparatus the ore pulp ejected froma dpit fice imp n es a a st ba fi na' su face and thereby forms aminefahbearing l ia fil freth l ec n me n ope a v y aas e ted wi Saecept l testimony whereof :Iafiix my signature.

alw ys PA HFW mai-

